Function keys don't work

If your F<num> keys do not work, this is probably because the kernel driver for the keyboard has defaulted to using the media keys and requiring you to use the Fn key to get to the F<num> keys. To change this behaviour, you have to change a driver setting. Do the following as root:

echo 2 > /sys/module/hid_apple/parameters/fnmode

If it tells you that the file doesn't exist, you probably have an older kernel and will have to do the following instead:

echo 2 > /sys/module/hid/parameters/pb_fnmode

Place whichever command worked for you in /etc/rc.local to make the setting permanent.